can you tile over tile?

[principalitygirl]

Handyman has suggested we do this as the quickest and easiest way of getting rid of the one wall of our shower cubicle that is tiled with tiny mosaic tiles and miles of white grout that goes brown within a day of me spending hours scrubbing it clean! Anyone had any successes / failures with tiling over tile? Assume if done properly it should be fine but have a nagging doubt still...

I've heard many times that it's the best surface to tile onto.

you can, but consider that the tiling will now be (at least) twice as thick, so may look odd at exposed surfaces, or where it touches the shower tray.

I am especially keen on those sealing strips which have a rubbery fin pressed on the bath and shower, and a rigid rib which is tiled over. I don't know if you would be able to use that, or would have to rely on the usual gobbet of mouldy sealant.

We have lived in our house for 4 years and my mum noticed when she was here the other week that that is exactly what we have in our bathroom: tiles on top of tiles. We had not noticed; they look neat enough BUT it means that there is little 'edge' around the bath (I hadn't realised this was why!). This has been a right old pain trying to seal behind the taps as there is basically no space between the tiles and the back of the tap, so the sealant is continually failing (because you can't do a neat line without it being an extremely thin one). So I'd consider how it would look around the edges before you do it.

It'll be cheaper to get the handyman to tile over your existing tiles as it can take a while to remove the old tiles. You could remove the old ones yourself, which in my opinion should be a better result for presumably the same cost.

You CAN, but unless the tiles underneath and really sound then they can fall off and bring the new tiles with them. It also depends on the type of wall- if it's chipboard and not brick, then the weight of 2 depth tiles can be an issue as well.

We have just removed tiles across a whole large wall in the bathroom- floor to ceiling- and the tiler spent a lot of time ensuring the wall was sound enough to take new tiles- sometimes they need boarding over if the wall is chipboard and likely to flex.

You CAN do it, but it's no good in the long run, unless it's very well sealed.
We had a shower cubicle in our first vet rented flat. All nice clean white tiles, obviously newly done for our (6m) lease.
One day I noticed around the bottom of the cubicle that the tiles were pointing outward - like a triangle.
I poked them back in with my foot and they all came crashing down. The new clean white ones AND old grey ones. The wall behind them was black with damp/mould. Obviously the weight and the wet environment was too much.

chipboard walls? I hope you mean plasterboard

There are special tile backing boards around now, especially good in shower cubicles as they stand up well to moisture.